Ben Watanabe of NESN explains further, writing that so much losing is weighing on the new Celtics coach:

Whatever we are, record-wise, we’re just not a very good basketball team. A good, old-fashioned butt kicking, that’s what it was. I don’t think I have to describe it all that much. I think we were all sitting there watching.

“Whatever we are” doesn’t quite describe it accurately—the Celtics are now 15-33 for the season and have lost 18 of their last 21 games, including their last three in a row.

Coincidentally, point guard Rajon Rondo has played six games since returning to the lineup after knee surgery and is averaging just 6.7 points and 5.7 assists per game—a mere fraction of his former glory. On Tuesday, Rondo was 3-of-13 from the floor in 27 minutes. Rondo's been sitting out the occasional game, as he eases his way back into regular-season form.

Stevens is in his first year as a head coach in the NBA, and replacing Doc Rivers is no easy task. Add the fact that Paul Pierce and Kevin Garnett were traded away, and it’s hard to really point the finger at any one party—nobody was exactly expecting the Celtics to compete for a championship this year.

Still, for a guy who was supposedly the master of positivity, this new grumpy persona is a bit of a shock.

Maybe it’ll light a fire under his team. Maybe it’s just a sign of things to come for the rest of a losing season. Welcome to the NBA, coach!